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Question:

How is the PLC and the relay connected?

For convenience, the above figure. Relay Model: JZX-22F / 2Z with light. First ask this thing is the relay or contactor? Can it be used I would like to use PLC (Siemens s7-300 (cpu314c-2pn / dp)) simple control motor start and stop. Ask three-phase power into the line A / B / C were connected with the relay, and then U / V / W and how to connect that a few points? After programming 13,14 terminal with PLC which several terminals connected? I do not know what I asked right, but hope you can definitely answer me, thank you. There is I want to give the switch signal can not be sent to the PLC through the host computer, plc signal sent to the relay after the implementation? I look forward to your answer

Answer:

Obviously this relay is not suitable for your circuit relays are two normally open two normally closed What you need is the contactor console directly connected to the PLC output is used to control the three-phase closure
You are the middle of the relay, 13 14 is the relay coil ah, the relay coil is AC220 then 13 then PLC output, 14 then N line, FireWire access PLC COM side, with the relay to open the open contactor Of the coil, ABC UVW are connected to the AC contactor on the main contact
Three-phase power can not receive you on this relay, because you can only connect the relay coil DC, then AC power does not work. Obviously this figure is the relay, 13,14 pin is its coil pin, 14 then positive, 13 negative. 1 and 9, 4 and 12 are normally closed contacts, 5 and 9, 8 and 12 are normally open contacts. A single relay can not achieve your function, you have to add a contactor. Relay 14 feet connected to a PLC output point, 13 feet to receive the public negative PLC. And then with a pair of normally open contacts 5 and 9 (or 8 and 12) connected to the contactor coil; contactor into the line side of the ABC three-phase electric, the outlet is connected to the motor UVW. This is the case, the PLC signal to the relay, the relay coil live, normally open point closed so that the contactor coil live, contactor coil live, normally open point closed three-phase electrical connected to the motor, the motor running. Can be sent to the PLC signal through the host computer, and then PLC and then control the relay, relay control contactor, contactor control motor running.
This is a relay Complete the process you say is the drop: to add a contactor, PLC output connected to the relay coil, relay contact control contactor coil, contactor main contact control motor. If the relay output PLC wiring is very simple, and their group of contacts are parallel, the public connection point is COM, the landlord to the output as a contact on it.

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